Characterization, Expression Pattern and Function of the Medaka (Oryzias Latipes) gasz Gene

Abstract

GASZ ENCODES A GERM CELL-SPECIFIC PROTEIN CONTAINING FOUR ANKYRIN REPEATS, A STERILE-A-MOTIF, AND A BASIC LEUCINE ZIPPER. IN THIS STUDY, THROUGH DATABASE MINING AND RT-PCR, WE ISOLATED A CDNA FRAGMENT IN MEDAKA, THE CDNA IS 1.4KB IN LENGTH AND CONTAINS A FULL ORF, ENCODING 485 AMINO, POSSESSING THE CHARACTERISTIC MOTIFS OF GASZ HOMOLOGUES AND SHARING HIGH IDENTITIES WITH GASZ HOMOLOGUES, DESIGNED AS OGASZ. RNA IN SITU HYBRIDIZATION AND IMMUNOHISTOCHEMISTRY SHOW THAT MEDAKA GASZ IS PREFERENTIALLY EXPRESSED IN THE EARLY STAGES OF GERM CELLS DURING GAMETOGENESIS, MATERNALLY SUPPLIED TO DEVELOPING EMBRYOS AND CONCENTRATES IN PRIMORDIAL GERM CELLS (PGCS). IMPORTANTLY, OGASZ AND OVASA RNA CO-LOCALIZE IN PGCS, SUPPORTING THAT OGASZ IS A NEW GERM CELL MARKER IN MEDAKA. THE PRELIMINARY FUNCTIONAL ANALYSIS BY MORPHOLINO KNOCKDOWN EXPERIMENT SHOWS THAT THE INHIBITION OF OGASZ TRANSLATION LED TO A DECREASE IN PGC NUMBER DURING EARLY STAGES OF MEDAKA EMBRYOS. THIS IS THE FIRST DIRECT EVIDENCE THAT